Judge Assign page should display the tasks of the user_id provided in the URL

[hschallhorn]

Description

In "SCM: SCM Team can view Judge's Assign Queue #12423", we introduced the start of "viewing the queue of another user". Before this, although the url provided another user's id, a judge's assign queue would show the task of the signed in user. Now, the judge's css_id is provided to show that judge's tasks. This is redundant as the provided user_id should match the provided css_id. Before work on "Give judge assign queues human readable urls #13433" can be completed, we should only be relying on the provided user id to determine what user's tasks to show on the page

Acceptance criteria

• /queue/189/assign shows the tasks for user 189, regardless of who is signed in.

Extra

Related to #13237

[lomky]

what is this chart?

1 | 
2 | |||
3 | |||||||||
5 | 
8 | 

Estimating at a 3.

Might be a 2 because all we're doing is merging the ids to be used in the same way. Need to return the user css_id as needed on the front end.
Might be a 3 to refactor our existing solution.